Minimally invasive surgical procedures including percutaneous techniques are known that have attempted to overcome the above drawbacks of open surgery. Minimally invasive surgical procedures minimize disruption and trauma to the body to reduce recovery time and post-operative pain. For example, minimally invasive surgical techniques are employed for spinal and neurosurgical applications to access surgical sites within the body adjacent vital intervening tissues, in an effort to avoid damaging such vital tissues.
Surgical instruments, such as a penetrating sleeve, cannula or guide, pass through tissue walls of the body to gain access to anatomical cavities and provide access to a surgical site for surgical treatment of, for example, spinal disorders including fusion, fixation, discectomy, laminectomy and implantable prosthetics. Such instruments can be stabilized and oriented to maintain position for access to tissue and other body structures under treatment within the anatomical cavity. This disclosure describes an improvement over these prior art technologies.